(1) Field of the Invention
The present invention relates to a method and a device for controlling at least one piece of equipment, and in particular it relates to a control device for an aircraft. More particularly, the control device comprises a touch screen.
The present invention thus lies in the field of man-machine touch interfaces for aircraft.
(2) Description of Related Art
Certain flight procedures require crew to interact with one or more control devices.
These control devices may involve commands that are said to be “virtual” insofar as the commands are represented by symbols displayed on a touch screen. The touch screen then embodies one or more commands that can be operated by touching the touch screen.
Such a control device may represent a combination of a plurality of conventional instruments. The touch screen then displays different commands as a function of the piece of equipment that is to be controlled. The control device is thus a multifunction device.
Touch screen control devices are particularly advantageous because of their ergonomics.
Nevertheless, movements of crew members in the aircraft can then lead to untimely interactions with such touch screen control devices. In flight, a pilot might for example exert pressure on a touch screen without meaning to, and thereby give rise to untimely operation of a piece of equipment or a system.
In order to avoid such a situation, the prior art provides various solutions.
In order to avoid involuntary interaction with a touch screen, the system may include a device for locking and unlocking the touch screen.
Although effective, unlocking a touch screen prior to each interaction can constitute an element that is disturbing for a pilot who is busy with other tasks. That method tends to increase the workload on the pilot. Under such circumstances, the pilot is more likely to commit errors, e.g. by attempting to interact with a touch screen while it is still locked.
Other devices tend to require each of the commands embodied on a touch screen to be unlocked individually.
That method can also significantly increase the workload on a pilot.
In this context, Document EP 1 964 022 discloses a method for unlocking a touch screen by moving an unlock image along a path.
Document US 2014/0062893 describes a system and a device for reducing the probability of a touch screen being activated accidentally.
Document US 2014/0062893 describes a first mode of operation by comparing a profile with a prerecorded profile, a second mode of operation that is interactive with visual feedback, and a third mode of operation where the level of performance is associated with the type of function allocated to the man-machine interface being controlled.
Document EP 1 360 572 B1 is far removed from touch screens, since it refers to a computer. That document relates to a programmable three-state icon that is displayed on a computer display. The first state corresponds to a passive state. The second state is actuated to start an action on the computer, so as to avoid initiating involuntary an action on the computer, by selecting successively the first state and the second state.
When user selection causes the action to start, the icon changes to the third state.
Document EP 2 587 350 describes a method of determining whether an order given by touching the touch screen is valid. That method determines the validity of such an action as a function of a biomechanical signature.
Document FR 2 853 095 relates to a safe man-machine interface device for a touch screen.
That document relies on the principle of a physical locking button as applied to a touch screen.
Document FR 2 911 409 describes a method and a system for enabling safe control from a touch screen.
That document suggests using three symbols for one command.
Document U.S. Pat. No. 8,633,913 B1 proposes a control and display system adapted to a touch screen having a plurality of data formats.
Documents EP 0 562 929, US 2009/063967, and EP 2 600 108 are also known.